Catalytic contacting unit



Jan. 10, 1956 HOUDRY 2,730,434

CATALYTIC CONTACTING UNIT Filed May 1, 1950 3 Sheets-Sheet l Ila llb

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Jan. 10, 1956 E. J. HOUDRY 2,730,434

CATALYTIC CONTACTING UNIT Filed May 1. 1950 5 Sheets-Sheet 2 75:4 Il600000666 A F/G4. Q

INVENTOR. F EUGENE J, HOUDRV ATTORNEY.

Jan. 10, 1956 INVENTOR. EUGENE J1 HOUDR) .xgtq 0C AITORNEY.

United States Patent CATALYTIC CONTACTING UNIT Eugene J. Houdry,Ardmore, Pa., assignor to Oxy-Catalyst, Inc., a corporation ofPennsylvania Application May 1, 1950, Serial No. 159,191

Claims. (Cl. 23-288) and support of contacting and catalytic elements.

Another object is to support the contacting and catalyticielernents insuch a manner that friction and attrition are avoided thereby to prolongthe life and effective use of 'such elements.

Another object is to provide the contacting elements in units forconvenient handling, assembly, impregnation fwith catalysts, andmounting, while furnishing a desired degree of flexibility as to number,disposition, and arrangement of elements for control of temperature,pressure, and time of contact.

.Other objects and advantages will be apparent from the detaileddescription which follows.

In accordance with the present invention the fluid contacting orcatalytic elements are formed in units or assemblies which may beutilized individually or stacked adjacent to or upon one another likebricks. By preference, the parts of these units or assemblies are ofdense hard material having any suitable or desired degree of porosity orabsorptivity, usually slight or low, such as ceramic material includingporcelain, and the latter may be of the type used for the cores of sparkplugs, and which has been heated to high temperatures of the order of2000" and above. The unitary structure comprises upper and lowerapertured members or plates maintained in fixed spaced relation by oneor more posts or spacer bars, the apertures in the members or platesbeing disposed in alignment for the individual insertion of elongateelements in the form of rods or sticks. Each element is by preferencesecured at one end to one of the end members or plates and is endwisemovable in the aperture therefor in the other member or plate so as toavoid breakage from expansion and contraction during temperaturechanges. Time and extent of contact of fluids is determined in part bythe number of elements mounted in the apertures in the end members ofeach unit and by the size, shape, arrangement and cross sectionalcontour of Fig. 3 is a longitudinal sectional view, taken on the line3-3 of Fig. 4, showing a modification of the invention;

Fig. 4 is an end elevational or top plan view of the unit shown in Fig.3, the left half of unit being without elements;

Fig. 5 is a perspective view on an enlarged scale of one form of elementfor mounting in the unit shown in Figs. 3 and 4;

Fig. 6 is a transverse sectional view on a still larger scale, thesection being taken on the line 66 of Fig. 5;

Fig. 7 is a plan or end elevational view similar to Fig. 4 of a modifiedform of unit, elements to fit the apertures being omitted;

Figs. 8 and 9 are perspective views on an enlarged I scale of elementsto be mounted in the unit of Fig. 7;

and

Fig. 10 is a transverse sectional view on a still larger scale on theline 10-10 of Fig. 9.

As shown in Figs. 1 and 2 the contacting or catalytic unit comprises apair of apertured end members or plates 11 in spaced relation to eachother and secured to a central spacer or post 12 to form a frame,adapted to support a multiplicity of contacting or catalytic elements13. As indicated in Fig. 2 elements 13 are round in cross section andextend between end members 11 and have their ends seated in alignedpairs of apertures 11a. Spacer or post 12 is square in cross section andextends through openings of the same configuration in end members orplates 11, inwardly directing bosses 11b on the latter insuring secureattachment between post 12 and members 11 and imparting strength andrigidity to the frame. Elements 13 are in the form of rods which areinserted endwise through aligned apertures 11a to be supportedindividually and independently of one another. By preference elements orrods 13 are cemented, glazed or otherwise anchored in the apertures ofone of endmembers 11 while care is taken to see that their other endsare freely slidable in the apertures of the other end member 11. Thisarrangement prevents breakage of elements 13 or of end members 11 whentemperature differences occur in the parts of the unit.

As indicated by Fig. 2 apertures 11a in members or plates 11 disposeelements 13 in rows with adjacent elements in staggered arrangement sothat fluids sent through this unit from the side, as in the direction ofthe arrow d on Fig. 1, are caused to flow over and around each element.

In the modification of the invention shown in Figs. 3-6 the lower endmember or plate 21 of the frame has its apertures 21a extending onlypartly therethrough to provide a positive stop for the lower ends ofelements 23 which are mounted in the frame by inserting them through theapertures 22a in upper end member or plate 22. A central spacer or post24 is attached at its ends to members or plates 21 and 22 to form theframe of the unit, the ends 24a of the spacer 24 being reduced in sizeto provide stop shoulders 24b to engage the inner faces of members 21and 22 as indicated in Fig. 3. As clearly shown by Figs. 4, 5 and 6elements 23 to be mounted in the frame of Fig. 3 are of teardrop orstreamlined design in cross section and the apertures 21a and 22a in endmembers or plates 21 and 22 are of complementary shape and are alldisposed in the same direction. Since the elements or rods, 23, arerounded at one vertical edge 23a and tapered toward the oppositevertical edge 23b (as shown in Figs. 4, 5 and 6) to produce astreamlined effect, they offer the possibility of a minimum pressuredrop in reactants passing thereover in the direction of movementindicated by arrow d of Fig. 4 and at the same time give the bestcontact of the reactants with the surfaces of elements 23 whileproducing a minimum of turbulence. The lower ends of elements 23 will besecured in apertures 21a of lower member or plate 21 by cementing,glazing or otherwise while their upper ends will be freely slidable inapertures 22a of upper member or plate 22.

Figs. 7, 8, 9 and 10 illustrate further modifications of the contactingunit and of the elements supported thereby, in this instance, forcreating turbulence and a greater period and extent of contact ofreactants with the elements. In the form shown in Fig. 7 there are twospacers or posts 34 (similar to spacer 24 of Figs. 3 and 4) to supportand hold end members or plates 31 (only one of which is shown) in spacedrelation. Apertures 31a to receive elements 33 (Fig. 8) or elements 36(Fig. 9 and Fig. 10) are rectangular in shape and are not only staggeredrelative to the apertures in adjacent rows (as in the modifications ofFigs. 1 and 2 and of Figs. 3 and 4) but are also zig-zagged to baflieand to create turbulence and frequent changes in direction in reactantssent through the unit from any side. In order to effect furtherturbulence and extended contact with the elements mounted in apertures31a the surfaces of the elements are made irregular or of increasedextent in any desired manner. One way to accomplish this is to form ribson the elements. Fig. 8 shows element 33 provided with a series of crossor transverse ribs 330 on its widest sides While element 36 of Figs. 9and 10 has longitudinally extending or vertical ribs 36:: on all itssides.

Element 33 is shown in Fig. 8 as having rectangular ends 33b loosely tofit apertures 31a in end members or plates 31 of Fig. 7. However, it isobvious that, if desired, the transverse ribs 33a may be formedthroughout the length of element 33 without interference with itsmounting in the frame of the unit or its use when so mounted. In asimilar manner the longitudinal or vertical ribs 36a of element 36 ofFigs. 9 and 10 may be extended to the veryends of the element, thuseliminating the rectangular ends 36b shown thereon, in which case theapertures 31ain members 31 could be made, if desired, to conform to thecross section of element 36 shown in Fig. 10. By providing rectangularapertures 31a in end members or plates 31 both elements 33 and 36 in anydesired distribution may be mounted in the same unit. As in thepreviously described forms of the invention the elements 33 and 36 willbe secured at one end to one of the end members or plates 31 while theirother ends are freely slidable in the apertures 31a of the other endmember or plate.

The various parts making up the herein described units may be of anysuitable or desired materials, catalytically active or inactive, and ifabsorbent, of any suitable or de sired degree of porosity, so as toassist or to promote any desired type of operation or reaction. One kindof material particularly adapted to units of the present invention isceramic material, such as porcelain. The latter can be readily molded,cast or extruded into the forms illustrated and can by composition andsubsequent firing be made of any desired degree of porosity in the rangeof substantially no or slight porosity to about 60% porosity. By firinginto the range of 2300 to 3900 F. it can be made stable both physicallyand chemically as well as catalytically inert. It is then useful as asupport, in or on which catalytic materials can be incorporated in anyknown or suitable manner as by dipping, immersing, spraying, etc.Bonding of the elements such as 13, 23, 33 and 36 to one of the endmembers or plates of the frame is frequently incidental to incorporatingor applying catalytic materials to the assembled unit, as by dipping thelatter up to but not including the top end member or plate (as 22 ofFig. 3), followed by heating step to decompose the solution or mixtureso as to deposit the catalytic material in active form in or on theframe and elements mounted therein. On the other hand, the individualparts making up the units may have catalytic material incor- 4 poratedtherein or deposited thereon prior to assembly of the unit.

The unit can be made of any desired size and the end members or platesmay be shaped as required to fit, or for use in, a particular reactionchamber. The elements may be in any desired number, form andarrangement. A square or rectangular shape for the end members orplates, as shown in Figs. 2, 4 and 7, is desirable for stacking orside-by-side disposition of units. Of the units shown on the drawings,that of Figs. 1 and 2 makes provision for 196 round elements or rods 13,the modification of Figs. 3 and 4 provides for 73 streamlined elementsor rods 23, while the modification of Fig. 7 will hold 63 elements orrods such as 33 and 36. One use of units of the type of Figs. 1 and 2 isset forth in my copending application Serial No. 117,490 filed September23, 1949.

In general in utilizing the unit as a support for catalysts, a firmlyadherent base or film of active alumina (or alternatively of magnesia,beryllia or thoria) may be applied in any suitable or desired manner tothe unit or its parts followed by impregnating such base or film withother and additional finely divided metals or oxides. Such a combinationand arrangement of catalytic materials has been found to becharacterized in many instances by exceptionally high activity for thepromotion of many reactions, both endothermic and exothermic, and to befurther characterized by long life. For example, for catalytic reactionsof the oxidation type, such as oxidation of CO to CO2, the base film ofalumina or the like should be impregnated with platinum, or silver, orcopper; for oxidation of S02 to $03, platinum or vanadium oxide shouldbe deposited on the base film; for synthesis of methane by the reactionof CO+3H2=CH4+H2O, cobalt or nickel should be added to the base film ofactive alumina or the like.

If the unit is to be used to promote a hydrogenation reaction, such asthe hydrogenation of fats, a nickel catalyst should be deposited on thebase film of active alumina. When the nickel hydrogenation of fats is inthe liquid phase, the parts of the unit should be formed of porcelain orthe like which is practically impervious or of extremely low porosity sothat only the catalytically active material deposited on the surface ofthe parts of the unit will contact the oil or fats undergoinghydrogenation. Separation of reactants can then be easily efiected withobvious economies and advantages.

Both oxidizing and hydrogenating reactions being exothermic, theliberation of heat diminishes as the reactants progress through thereaction zone. Consequently to efiect a uniform operation the rate ofreaction should be adjusted as the reaction progresses. Control of therate of reaction per unit volume of the reaction zone is readilyaccomplished by adjusting the number of elements in the catalytic unitsin accordance with the location of the units within the reaction zone.Thus the first unit, or first group of units, to be contacted by thereact.- ants in an exothermic operation would be provided with fewerelements and/ or in a more open arrangement than subsequent units so asto adjust the extent and rate of the reaction.

For catalytic cracking of petroleum, active alumina is first depositedon the parts of the unit followed by a deposition of silica; and foraromatization of naphtha, finely divided molybdenum oxide is depositedupon a base film of alumina. In these operations which are bothendothermic the rate of reaction changes as the hydrocarbon vapors flowthrough the catalytic zone, with the result that coke is not evenlydeposited on the catalyst, with the further result that duringregeneration, effected by burning off the coke, heat is liberatedunevenly, thusrendering control of temperature of the catalystdifiicult. Here again adjustment of the number and arrangement ofelements mounted in the contacting units of the present invention willbe efiective in establishing proper time and extent of contact tocontrol the rate of reaction.

The above examples indicate some of the catalytic reactions for whichthe contacting unit may be employed; others are synthesis of alcohol,oxidation of acetylene to acetone, dehydration of ethyl alcohol,hydrogenation of fuels,-destructive hydrogenation of mineral oils,desulphurization of crude oils in liquid phase, chlorination reactions,etc., and still others which will occur to those skilledin the art ofcatalysis.

From the above it will be apparent that the present invention provides acontacting or catalytic unit in which contacting or catalytic elementsmay be fixedly mounted 'so that each element is independent of theother, thereby avoiding friction and consequent damage to the elementsand partial or complete destruction of catalysts impregnated therein orapplied thereto in the form of films, that the elements are not incompact relationship with one anotherbut are spaced from one another sothat low pressure drops through the units are easily obtained and theproblem of excessive temperatures can be solved by adjusting the numberand distribution of elements in each unit, and that the units andelements therefor may be formed and arranged to produce a minimum ofturbulence and contact or great turbulence and extensive contact therebyeffectively to control the rate and extent of a catalytic or contactingreaction.

While the invention has been herein shown and described in connectionwith certain preferred forms of apparatus, it is to be understood thatthe invention is not restricted to the specific features thereof butcovers all changes, modifications and adaptations within the scope ofthe appended claims.

I claim as my invention:

1. A catalytic unit through which a fluid may flow comprising a pair ofend members secured to one another in spaced relation by a single postextending between said members and to which said members are rigidlyfastened, and a plurality of elongated elements extending between saidend members and supported at both ends thereby, each .of said elementsproviding a surface of catalytic material exposed to the flow of fluidpassing through the unit, said unit being open laterally for the passageof fluid therethrough in a direction transverse to said elongatedelements.

2. A catalytic unit according to claim 1 in which said elements are ofceramic material.

3. A catalytic unit according to claim 1 in which the surfaces ofcatalytic material are provided by coatings on said elements.

4. A catalytic unit through which a fluid may flow comprising a pair ofend members secured to one another in spaced relation by a single postextending between said members and to which said members are rigidlyfastened, and a plurality of elongated elements extending between saidend members and supported at both ends thereby, said elements beingdisposed in rows with the elements in each row in staggered relationwith the elements in adjacent rows, and each of said elements providinga surface of catalytic material exposed to the flow of fluid passingthrough the unit, said unit being open laterally for the passage offluid therethrough in a direction transverse to said elongated elements.

5. A catalytic unit through which a fluid may flow comprising a pair ofend members secured to one another in spaced relation by a single postextending between said members and to which said members are rigidlyfastened, and a plurality of elongated elements extending between saidend members and supported at both ends thereby, each of said elementshaving at least one end free to move longitudinally with respect to anend member, each of said elements providing a surface of catalyticmaterial exposed to the flow of fluid passing through the unit, saidunit being open laterally for the passage of fluid therethrough in adirection transverse to said elongated elements.

. 6. A catalytic unit through which a fluid may flow comprising a pairof end members secured to one another in spaced relation by a singlepost extending between said members and to which said members arerigidly fastened, and a plurality of elongated elements extendingbetween said end members and supported at both ends thereby, each ofsaid elements having in transverse section rounded and tapered portionsforming a streamlined contour to minimize turbulence in the flowingfluid, and each of said elements providing a surface of catalyticmaterial exposed to the flow of fluid passing through the unit, saidunit being open laterally for the passage of fluid therethrough in adirection transverse to said elongated elements.

7. A catalytic unit through which fluid may. flow which comprises a pairof platelike end members, a single post for rigidly positioning said endmembers in parallel, spaced relaionship, said end members beingcentrally fastened to said post at either end thereof, a plurality ofelongated elements extending between said end members and supported atboth ends thereby, at least one end of each of said elements being freeto move longitudinally with respect to one of said end members, each ofsaid elements providing a surface of catalytic material exposed to theflow of fluid passing through the unit, said unit being open laterallyfor the passage of fluid therethrough in a direction transverse to saidelongated elements.

8. A multi-unit catalytic assembly for providing an extended area ofcatalytic surface, each unit of said assembly comprising a pair of endmembers secured to one another in spaced relation by a single postextending between said members and to which said members are rigidlyfastened, and a plurality of elongated elements extending between saidend members and supported at both ends thereby, each of said elementsproviding a surface of catalytic material exposed to the flow of a fluidpassing through the unit, said units being open laterally for thepassage of fluid therethrough in a direction transverse to saidelongated elements.

9. A catalytic unit for carrying out high temperature catalyticreactions which comprises a pair of plate-like end members composed ofceramic material, a single post composed of ceramic material for rigidlypositioning said end members in parallel, spaced relationship, said endmembers being centrally fastened to said post at either end thereof, aplurality of elongated, rod-like, elements composed of ceramic materialextending between said end members and supported at both ends thereby,at least one end of each of said elements being free to movelongitudinally with respect to one of said end members, each of saidrod-like elements being provided with a relatively thin film ofcatalytic material exposed to the flow of fluid passing through theunit, said unit being open laterally for the passage of fluidtherethrough in a direction transverse to said elongated elements.

10. A unit in accordance with claim 9 in which said end members, saidpost, and said rod-like elements are composed of a dense, relativelyimpervious porcelain.

11. A ceramic unit for use in carrying out high temperature reactionswhich comprises a pair of plate-like end members of ceramic material, asingle post of ceramic material for rigidly positioning said end membersin parallel, spaced relationship, said end members being centrallyfastened to said post at either end thereof, a plurality of elongatedrod-like elements composed of ceramic material extending between saidend members and supported at both ends thereby, at least one end of eachelement being free to move longitudinally with respect to one of saidend members, said unit being open laterally for the passage of fluidtherethrough in a direction transverse to said elongated elements.

12. A unit constructed in accordance with claim 11 in which said endmembers, said post, and said rod-like elements are composed of arelatively dense and impervious porcelain.

13. A unit constructed in accordance with claim 11 in which saidrod-like elements have in transverse section rounded and taperedportions forming a streamlined contour to minimize turbulence in thefluid flowing through said unit.

14. A catalytic unit adapted for high temperature catalytic reactionswhich comprises a pair of plate-like end members composed of ceramicmaterial, a single post composed of ceramic material for rigidlypositioning said end members in parallel, spaced relationship, said endmembers being centrally fastened to said post at either end thereof, aplurality of elongated rod-like elements extending between said endmembers and supported at both ends thereby, said elements being disposedin rows With the elements in each row in staggered relation with respectto the elements in adjacent rows, each of said elements having intransverse section rounded and tapered portions forming a streamlinedcontour to minimize turbulence in the flowing fluid, at least one end ofeach of said elements being free to move longitudinally with respect toone of said end members, each of said rod-like elements being providedwith a relatively thin film of catalytic material exposed to the flow offluid passing through the unit, said unit being open laterally for thepassage of fluid therethrough in a direction transverse to saidelongated elements.

15. A unit constructed in accordance with claim 14 in which saidelongated rod-like elements are supported in apertures provided in saidplate-like end members.

References Cited in the file of this patent UNITED STATES PATENTS EldredNov. 5, 1912 Lowe et al. Sept. 7, 1920 Selden Nov. 1,1927 Duke Mar.6,1934 Houdry Jan. 15, 1935 Houdry Jan. 15, 1935 Houdry Jan. 15, 1935Snow Feb. 5,1935 Harrison Mar. 5,1935 Pohl Jan. 21,1936 Prickett June22, 1937 Finn, Ir. Feb. 1, 1938 Bejarno Dec. 6,1938 Shapleigh Sept. 26,1939 Simpson et al Jan. 2, 1940 McCausland July 30, 1940 Houdry Sept.9,1941 Foster Sept. 24,1946

OTHER REFERENCES Chem. Eng. Catalog, l9421943, page 544, publ. byReinhold Publishing Co., N. Y. C.

1. A CATALYTIC UNIT THORUGH WHICH A FLUID MAY FLOW COMPRISING A PAIR OFEND MEMBERS SECURED TO ONE ANOTHER IN SPACED RELATION BY A SINGLE POSTEXTENDING BETWEEN SAID MEMBERS AND TO WHICH SAID MEMBERS ARE RIGIDLYFASTENED, AND PLURALITY OF ELONGATED ELEMENTS EXTENDING BETWEEN SAID ENDMEMBERS AND SUPPORTED AT BOTH ENDS THEREBY, EACH OF SAID ELEMENTSPROVIDING A SURFACE OF CATALYTIC MATERIAL EXPOSED TO THE FLOW OF FLUIDPASSING THROUGH THE UNIT, SAID UNIT BEING OPEN LATERALLY FOR THE PASSAGEOF FLUID THERETHROUGH IN A DIRECTION TRANSVERSE TO SAID ELONGATEDELEMENTS.